Two and Plain Dealer reporters took on the car horn question, with notably different responses.
Opinion: When should you use your horn? Rarely, if you ask me
Is it illegal to beep your horn in Australia?
Will I get a fine if I beep my car horn? – The Sun
Roadshow: Horn honkers explain their behavior – The Mercury News
How to Turn Off a Car Horn
Ask a trooper: Horn-honking etiquette and Northwest drivers
Ask Dr. Dumb: Can Drivers Honk at Me While I'm Jogging? — Mark Remy's
What the Highway Code Says About Honking Your Horn
When is it legal to use the horn? What is honking etiquette?
No Constitutional Right To Honk Your Car Horn, Federal Court Says
NO HONK Please
How can honking be heard inside cars safely to warn drivers? - Quora
Honking your car horn: when is it ok? - Defensive Driving